1. Field of Invention
The present invention relates to a lamp and a light emitting diode tube thereof. The lamp can be electrically connected to a power source via one end of the light emitting diode tube; otherwise, the lamp can be electrically connected to the power source via a first conductive terminal of one end of the light emitting diode tube and a second conductive terminal of the other end of the light emitting diode tube.
2. Related Art
FIG. 1A is a schematic view showing a connection configuration of a conventional fluorescent lamp. The fluorescent lamp 9 includes a fluorescent tube 92, a magnetic ballast 93 and a starter 94. For small fluorescent tubes, they do not require high voltage to start the lamp. However, for larger fluorescent tubes, they require a substantial high voltage (in the range of a thousand volts) to start the lamp. The starter 94 is used to preheat the electrodes of two ends of the fluorescent tube 92. When starting the lamp, a glow discharge will appear over the electrodes of the starter. This glow discharge will heat the gas in the starter and cause the bi-metallic electrode of the starter to bend towards the other electrode. When the electrodes touch, the two filaments 95 of the fluorescent lamp and the ballast will effectively be switched in series to the supply voltage. This causes the filaments to glow and emit electrons into the gas column by thermal ion emission. Once the tube is struck, the impinging main discharge then keeps the cathode hot, permitting continued emission without the need for the starter to close. The starter does not close again because the voltage across the starter is reduced by the resistance in the cathodes and ballast. The glow discharge in the starter will not happen at the lower voltage so it will not warm and thus close the starter. Tube strike is reliable in these systems, but glow starters will often cycle a few times before letting the tube stay lit, which causes undesirable flashing during starting.
Light emitting diodes have many advantages such as saving electricity and protecting environment, and are used to replace conventional lighting devices to be the major light source in the future. FIG. 1B is a schematic view showing a connection configuration of a conventional light emitting diode lamp 8 adapted from the fluorescent lamp 9 in FIG. 1A. In the light emitting diode lamp 8, the starter 94 will be removed, and the magnetic ballast 93 will be kept for lighting on the light emitting diode tube 82.